cmd/compile: fixing writebarrier.go for -G=3

This is caused by some nodes didn't carry the real line number.
Noder1 wraps these node with ir.ParenExpr. To fix this issue,
wraps this node like what noder1 does.

Change-Id: I212cad09b93b8bf1a7adfad416d229d15711918a
Reviewed-on: https://go-review.googlesource.com/c/go/+/349769
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Keith Randall <khr@golang.org>

src/cmd/compile/internal/noder/expr.go

@@ -390,9 +390,10 @@ func (g *irgen) compLit(typ types2.Type, lit *syntax.CompositeLit) ir.Node {
 			} else {
 				key = g.expr(elem.Key)
 			}
-			exprs[i] = ir.NewKeyExpr(g.pos(elem), key, g.expr(elem.Value))
+			value := wrapname(g.pos(elem.Value), g.expr(elem.Value))
+			exprs[i] = ir.NewKeyExpr(g.pos(elem), key, value)
 		default:
-			exprs[i] = g.expr(elem)
+			exprs[i] = wrapname(g.pos(elem), g.expr(elem))
 		}
 	}
 

src/cmd/compile/internal/noder/noder.go

@@ -1537,7 +1537,7 @@ func (p *noder) mkname(name *syntax.Name) ir.Node {
 	return mkname(p.name(name))
 }
 
-func (p *noder) wrapname(n syntax.Node, x ir.Node) ir.Node {
+func wrapname(pos src.XPos, x ir.Node) ir.Node {
 	// These nodes do not carry line numbers.
 	// Introduce a wrapper node to give them the correct line.
 	switch x.Op() {
@@ -1547,13 +1547,17 @@ func (p *noder) wrapname(n syntax.Node, x ir.Node) ir.Node {
 		}
 		fallthrough
 	case ir.ONAME, ir.ONONAME, ir.OPACK:
-		p := ir.NewParenExpr(p.pos(n), x)
+		p := ir.NewParenExpr(pos, x)
 		p.SetImplicit(true)
 		return p
 	}
 	return x
 }
 
+func (p *noder) wrapname(n syntax.Node, x ir.Node) ir.Node {
+	return wrapname(p.pos(n), x)
+}
+
 func (p *noder) setlineno(n syntax.Node) {
 	if n != nil {
 		base.Pos = p.pos(n)

src/cmd/compile/internal/noder/stmt.go

@@ -37,7 +37,7 @@ func (g *irgen) stmt(stmt syntax.Stmt) ir.Node {
 	case *syntax.BlockStmt:
 		return ir.NewBlockStmt(g.pos(stmt), g.blockStmt(stmt))
 	case *syntax.ExprStmt:
-		return g.expr(stmt.X)
+		return wrapname(g.pos(stmt.X), g.expr(stmt.X))
 	case *syntax.SendStmt:
 		n := ir.NewSendStmt(g.pos(stmt), g.expr(stmt.Chan), g.expr(stmt.Value))
 		if n.Chan.Type().HasTParam() || n.Value.Type().HasTParam() {

src/cmd/compile/internal/noder/transform.go

@@ -404,6 +404,10 @@ func assignconvfn(n ir.Node, t *types.Type) ir.Node {
 		return n
 	}
 
+	if n.Op() == ir.OPAREN {
+		n = n.(*ir.ParenExpr).X
+	}
+
 	if types.IdenticalStrict(n.Type(), t) {
 		return n
 	}

test/run.go

@@ -2184,8 +2184,6 @@ var types2Failures32Bit = setOf(
 )
 
 var g3Failures = setOf(
-	"writebarrier.go", // correct diagnostics, but different lines (probably irgen's fault)
-
 	"typeparam/nested.go", // -G=3 doesn't support function-local types with generics
 )